Siemens SIMATIC ST-1500 Function Manual page 174

Substitute value for DQ0 (Compact CPU)
You can use this parameter to specify the value to be output for a STOP of the Compact
CPU in the feedback interface for DQ0 in the context of the "Substitute value for DQ0"
behavior.
Note
In operating mode "Operating with "Counting and measurement" technology object", you
assign this parameter using the technology object.
Substitute value for DQ1
This parameter lets you specify which value the technology module is to output to the digital
output DQ1 in the event of a CPU STOP under "Output substitute value".
Note
In operating mode "Operating with "Counting and measurement" technology object", you
assign this parameter using the technology object.
Diagnostic interrupts (TM Count and TM PosInput)
The technology module can trigger additional diagnostic interrupts when you enable the
diagnostic interrupts in the basic parameters. These diagnostic interrupts are processed in
an interrupt OB.
Enable diagnostic interrupt on wire break
You use this parameter to specify whether a diagnostic interrupt is to be triggered in the
event of wire breaks of the utilized signals for the following encoders:
● Push-pull 24 V encoder (Page 67)
● RS422 encoder (Page 69) (also monitored for short-circuits and offset voltages)
● SSI absolute encoder (Page 71) (also monitored for short-circuits and faulty voltages)
Note
If you use an encoder with a different sensor type or interface standard, wire break cannot
be detected.
Counting, measurement and position detection
Function Manual, 12/2017, A5E32009889-AG
Using the module
5.1 Using the technology module
173